Knowledge, attitudes, and practice related to tooth loss and dentures among patients with dental arch deficiencies.

BACKGROUND: Tooth loss is a common problem that affects many people worldwide. Exploring knowledge, attitude, and practice (KAP) among patients can identify barriers and challenges in following recommended practices, providing valuable insights for dental healthcare providers, policymakers, and researchers. This study aimed to explore the KAP of patients with dental arch deficiencies regarding tooth loss and dentures. METHODS: This web-based, cross-sectional study was conducted among patients with dental arch deficiencies using a self-designed questionnaire. RESULT: 3166 valid questionnaires were included. Participants' mean KAP scores were 6.84 ± 2.27 (possible range: 0 ~ 12), 39.4 ± 3.72 (possible range: 9 ~ 45), and 27.7 ± 4.36 (possible range: 8 ~ 40), respectively. Multivariable logistic regression analysis showed that knowledge (OR = 1.383), employed (OR = 1.805), family history (OR = 2.158), and treatment (OR = 1.683) were independently associated with attitude. Moreover, knowledge (OR = 1.239), attitude (OR = 1.250), female (OR = 0.619), age (OR = 0.967), college/bachelor (OR = 0.373), and master and above degree (OR = 0.418), employed (OR = 0.554) or student (OR = 0.434), with 10,001-20,000 Yuan household income per month (OR = 0.492), have been married (OR = 0.609), smoking (OR = 0.595), drinking (OR = 0.397), disease duration (OR = 0.972), with family history (OR = 1.676), and with treatment (OR = 3.492) were independently associated with practice (all P < 0.05). CONCLUSION: Patients with dental arch deficiencies have insufficient knowledge, positive attitudes, and moderate practice toward tooth loss and dentures, which might be affected by multiple demographic factors.

Three-Dimensional Anthropometric Analysis of the Effect of Lip Reconstructive Surgery on Children with Cleft Lip and Palate at Three Different Times.

OBJECTIVES: This investigation aimed to assess the optimal timing for lip repair in children with cleft lip and palate via 3D anthropometric analysis to evaluate their maxillofacial structures. METHODS: The sample comprised 252 digitized dental models, divided into groups according to the following timing of lip repair: G1 (n = 50): 3 months; G2 (n = 50): 5 and 6 months; G3 (n = 26): 8 and 10 months. Models were evaluated at two-time points: T1: before lip repair; T2: at 5 years of age. Linear measurements, area, and Atack index were analyzed. RESULTS: At T1, the intergroup analysis revealed that G1 had statistically significant lower means of I-C', I-C, C-C', and the sum of the segment areas compared to G2 (p = 0.0140, p = 0.0082, p = 0.0004, p < 0.0001, respectively). In addition, there was a statistically significant difference when comparing the cleft area between G2 and G3 (p = 0.0346). At T2, the intergroup analysis revealed that G1 presented a statistically significant mean I-C' compared to G3 (p = 0.0461). In the I-CC' length analysis, G1 and G3 showed higher means when compared to G2 (p = 0.0039). The I-T' measurement was statistically higher in G1 than in G2 (p = 0.0251). In the intergroup growth rate analysis, G1 and G2 showed statistically significant differences in the I-C' measurement compared to G3 (p = 0.0003). In the analysis of the Atack index, there was a statistically significant difference between G1 and the other sample sets (p < 0.0001). CONCLUSION: Children who underwent surgery later showed better results in terms of the growth and development of the dental arches.

Comparative Analysis of Four Different Intraoral Scanners: An In Vitro Study.

(1) Background: Intraoral scanners undergo rapid advancements in hardware and software, prompting frequent updates by manufacturers. (2) Aim: This study aimed to quantitatively assess the precision of full dental arch digital impressions obtained from four different intraoral scanners: Trios 5-3SHAPE, Copenhagen, Denmark, CEREC Primescan- Dentsply Sirona, New York, NY, USA, Planmeca Emerald S-Planmeca Oy, Helsinki, Finland, and Medit i700-Medit Corp, Seoul, Republic of Korea. (3) Methods: A maxillary virtual dental model (digital master model) was created in accordance with ISO standard 20896-1. Subsequently, a 3D-printed model was obtained from the master model's STL file and scanned 15 times consecutively with each scanner. STL files were aligned with the master model's STL using Medit Link-Medit Design software v.3.1.0. The accuracy was evaluated by measuring deviations in micrometers between each scanner's scans and the master model. (4) Results: The study revealed variations in accuracy ranging from 23 to 32 µm across scans of the same dental arch, irrespective of the scanner used and scanning strategy employed. The anterior regions exhibited higher precision (Mean Absolute Deviation of 112 µm) compared to the posterior regions (Mean Absolute Deviation of 127 µm). Trios 5 demonstrated the smallest deviation (average 112 µm), indicating superior accuracy among the scanners tested. Emerald S and Medit i700 exhibited balanced performance (average 117 µm and 114 µm, respectively), while Primescan consistently displayed high deviation (average 127 µm). (5) Conclusions: Based on clinically accepted thresholds for accuracy in intraoral scanning, which are typically 200 µm for full arch scans, Trios 5 surpasses these benchmarks with its average deviation falling within the 200 µm range. Emerald S and Medit i700 also meet these standards, while Primescan, although showing high overall deviation, approaches the upper limit of clinical acceptability. Considering the limitations of an in vitro investigation, the findings demonstrate that each intraoral scanner under evaluation is capable of reliably and consistently capturing a full arch scan for dentate patients.

Comparative analysis of the influence of the shapes and dimensions of dental arches on the morphotopogeometric characteristics of the facial area.

OBJECTIVE: Aim: The aim of the article is a comparative analysis of the main aspects of existing medical and diagnostic measures in patients with abnormal types of occlusal relationships and methods of mathematical and graphic reproduction of the shape of the dental arches, taking into account the individual characteristics of the maxillofacial area. PATIENTS AND METHODS: Materials and Methods: The search for relevant publications related to the objective topic was carried out through scientific databases: Scopus, PubMed, BVS and Scielo. CONCLUSION: Conclusions: The analysis of regression models of the reproduction of individual characteristics of the dental arch of the jaws will avoid errors that occur when comparing the actual sizes with their statistical norm, which will allow to correctly determine the proportionality and ratio of dif f erent departments of the dental and jaw system, the necessary amount of orthodontic measures in the treatment of anomalies of the dental arches.

Relationship between the mandibular curve of Spee and the maxillary compensating curve with dentoskeletal morphology : A cross-sectional study in Chinese young adults with normal occlusion.

PURPOSE: The purpose of this cross-sectional study was to use multiple regression analysis to evaluate the relationship between the mandibular curve of Spee (COS) and the maxillary compensating curve with dentoskeletal morphology in young Chinese adults with normal occlusion. METHODS: This study comprised 62 young adults (31 males, mean age: 24.1 ± 2.2 years; 31 females, mean age: 23.3 ± 3.3 years) with Angle class I normal occlusion. For every subject, intraoral scan models of the maxillary and mandibular arches and lateral cephalograms were acquired. The depth of the COS and compensating curve were assessed on the intraoral scan models. Multiple dental arch dimensional and cephalometric variables were screened by univariate analysis. Subsequently, a multiple linear regression model (forward stepwise selection) was constructed to determine which variables were significantly correlated with the two curve depths. RESULTS: In the mandible, the COS depth was deepest at the mesiobuccal cusp of the first molar. Overjet, mandibular arch width and mandibular-occlusal plane angle significantly correlated with the COS depth (P < 0.05), accounting for 33.1% of the variation in the mandibular COS. In the maxilla, the deepest point of the compensating curve was at the distobuccal cusp of the first molar. Mandibular arch perimeter and overbite significantly correlated with the maxillary compensating curve (P < 0.05), explaining 23.3% of the variation. CONCLUSIONS: Overjet, overbite, mandibular-occlusal plane angle, mandibular arch width and perimeter should be considered when reconstructing occlusal curves in clinical orthodontic treatment and in prosthetic restoration.

Cleft Laterality Dental Arch Relationship Outcomes for Children with Unilateral Cleft Lip and Palate in New Zealand.

OBJECTIVES: To investigate cleft laterality dental arch relationship outcomes of children with non-syndromic complete unilateral cleft lip and palate (UCLP) in New Zealand. DESIGN: A retrospective nationwide study. SETTINGS: Virtual 3D orthodontic study models collected prior to undertaking secondary alveolar bone grafting. PARTICIPANTS: A total of 104 patients with UCLP (L = 80: R = 24). OUTCOME MEASURES: Four calibrated assessors used the GOSLON Yardstick and 100 mm Visual Analogue Scale (VAS) to score the randomised models on 2 separate assessment sessions. Weighted Kappa were used to determine the intra/inter-rater reliability for the GOSLON and correlations for the VAS. RESULTS: Intra-rater reliability ranged from 0.57-0.88 (GOSLON) and 0.45-0.93 (VAS). Inter-rater reliability ranged from 0.62-0.86 (GOSLON) and 0.64-0.93 (VAS).GOSLON scores for the left UCLP were 31.2% for good/very good; 26.3% for fair; 42.5% for poor/very poor while the right UCLP scored 8.3% for good/very good; 37.5% for fair; 54.2% for poor/very poor. The mean VAS for left and right UCLP were 53.4 (sd 22.5) and 44.6 (sd 17.1) respectively. Neither the GOSLON nor VAS differences reached statistical significance (both P = .08). CONCLUSIONS: From a clinical perspective right UCLP had worse dental arch relationship outcomes, however, these differences failed to reach statistical significance. Further studies using larger sample sizes are required to determine if cleft laterality is an important consideration when investigating UCLP dental arch outcomes.

Entire Dental Arch Mesial Movement after Extraction of Maxillary Right Central Incisor due to Root Fracture Treated with Temporary Anchorage Devices.

This case report describes a 19-year-old woman with skeletal Class I crowding and an unsalvageable maxillary right central incisor. She visited our clinic with the chief complaint of mobility of the maxillary right central incisor due to a traffic accident. After extraction of the maxillary right central incisor, the space was closed orthodontically. All the maxillary right teeth were moved mesially with an elastic chain attached to a palatal lever arm which was connected to palatal temporary anchorage devices (TADs). After orthodontic treatment had been completed, the maxillary right lateral incisor and peg-shaped left lateral incisor were restored with a porcelain laminate veneer. The maxillary right canine was morphologically reshaped and built up with composite resin. Consequently, esthetically ideal occlusion and functional lateral guidance with uncontacted molars were obtained. These results show that mesial movement of the entire dental arch with TADs is a useful orthodontic treatment option in patients in whom the maxillary central incisor has been extracted.

Association between shortened dental configurations and health outcomes: a scoping review.

This study mapped definitions of shortened dental configurations and health outcomes employed in association studies. A scoping review was conducted using the PubMed/Medline, Scopus, Web of Science, SciELO and Cochrane databases. Two trained researchers selected studies and extracted data. Studies that investigated the association between shortened dental configurations (exposure) and person-centered outcomes (general and oral health) related to health behavior (dietary patterns). Clinical outcomes were classified according to the International Classification of Functioning, Disability and Health and the International Classification of Diseases of the World Health Organization (WHO). Shortened dental configurations were defined as at least 20/21 teeth or the position of the teeth, including esthetics, dental occlusion and periodontal status (Eichner Index, Shortened Dental Arches, Functional Dentition Classification System, Posterior Occluding Pairs, Functional Tooth Units). The initial search resulted in 12,525 records in English, Portuguese and Spanish, 432 of which addressed the association of interest. General health (n = 203) and oral health (n = 201) were addressed in a similar number of studies. Most outcomes were related to general health (n = 184), the most frequent of which were endocrine, nutritional or metabolic diseases (n = 57) and mental functions (n = 26). Person-centered measures were addressed in 153 studies, most of which were about oral health and oral health-related quality of life (n = 62). Oral health outcomes were predominantly related to intake functions (n = 44) and diseases or disorders of the orofacial complex (n = 24). Dietary patterns (n = 43) and mortality (n = 38) were also studied. The cross-sectional design (n = 257) and non-probabilistic sampling (n = 218) were more frequent. The shortened dental configurations defined by the WHO were the most frequent in the studies (n = 206). The effects of shortened dental configurations have been investigated mainly in relation to endocrine, nutritional or metabolic diseases and measures of oral health-related quality of life. The findings point to a diversity of health outcomes assessed and substantial methodological variability.

Three-dimensional analysis of posterior tooth inclinations in transverse and sagittal relationships: A cross-sectional study.

OBJECTIVE: To compare tooth inclinations in different sagittal skeletal patterns and transverse maxillary relationships three-dimensionally. METHODS: A cross-sectional study carried out with 132 three-dimensional digital models in the complete permanent dentition divided into six groups (n=22); three groups with maxillary atresia: G1- skeletal class I, G2- skeletal class II and G3-skeletal class III; three groups without maxillary atresia: G4- skeletal class I; G5- skeletal class II and G6- skeletal class III. The comparison between the skeletal pattern was performed by the non-parametric tests of Kruskal Wallis and Dunn and between the groups by the non-parametric test of Mann Whitney. RESULTS: Subjects with skeletal class II and maxillary atresia had a greater lingual inclination of the maxillary teeth than those with class I and III; Subjects with skeletal class II without atresia had a less lingual inclination of the mandibular molars than the other classes (p<0.05). The maxillary premolars showed no variation in dental inclination with atresia, independent of the skeletal class in G1, G2, and G3 (p>0.05). The mandibular premolars showed that the groups without atresia G4, G5, and G6 presented no significant difference (p>0.05). Lower premolars in skeletal class III malocclusion individuals with atresia had a more negative inclination than the others. CONCLUSION: There is a difference in the inclination of posterior teeth between individuals with and without maxillary atresia and skeletal classes I, II, and III.

Customized planning of the visible maxillary arch width in harmony with interparopia width and smile width for female facial aesthetics.

BACKGROUND: The visible maxillary arch width (VAW) is an important aesthetic-determining feature. To date, there is no well-established methodology to determine the aesthetically optimal VAW in customized treatment planning. METHODS: In this study, the common traits of the dentofacial configuration were investigated in most attractive Asian and Caucasian female smiles. The smiling photo of a subject was digitally modified based on combined variations of VAW, smile width (SW), transverse facial dimensions (TFD), and vertical facial dimensions. These modified photos were assessed for aesthetics. The aesthetically essential parameters were identified, and their mathematic correlations and reference ranges were determined for different vertical facial patterns. Using the obtained results, a mathematic guidance was constructed for customized smile designing. The applicability of this guidance was tested in Asian females. RESULTS: The most attractive Asian and Caucasian female smiles have intraracial and interracial commonalities in the VAW-to-TFD ratios. The interparopia width (IPD) predominated over facial widths in determining well-matched VAW and SW. For optimal smile aesthetics, the VAW and SW were correlated as simulated by the formula 1.92 IPD ≤ VAW + 2.3 SW ≤ 2.17 IPD, plus the VAW-to-IPD ratio within 0.54 to 0.62 and the SW-to-IPD ratio within 0.61 to 0.71, ranges tailored to vertical facial patterns. This constitutes a mathematic guidance for customized planning of the aesthetically optimal VAW. This guidance was preliminarily validated to be applicable to Asian females. CONCLUSIONS: The VAW-to-TFD ratios were essential for Caucasian and Asian female smile aesthetics. The mathematic guidance could serve as a reference for customized smile designs for Asian females.

Prefabricated Trays Stock for Impression of Cleft lip and Palate Orthopedic Appliances: A Three-Dimensional Computational Analysis of Maxillary Jaws.

OBJECTIVE: This study aimed to propose digitally designed impression trays, for newborns with cleft lip and palate (CLP) defects, using the computer-assisted design and manufacturing (CAD/CAM) technique, based on measurements of width, length, and height made on processed and scanned plaster models. Thus, we will describe the different software and concepts that can be used for the design of these impression trays. DESIGN: A total of 59 plaster casts of newborn patients with CLP were collected and then scanned. After that, digital dental casts were three-dimensional (3D) evaluated, using precise anatomical landmarks. SETTING: The Maxillofacial Prosthodontics Team at the Dental consultation and treatment center in Rabat, Morocco. PATIENTS AND PARTICIPANTS: The study involved plaster casts of newborns with CLP, who had undergone presurgical neonatal treatment in the Maxillofacial Prosthodontics service in Rabat, Morocco. INTERVENTIONS: None. MAIN OUTCOME MEASURE(S): 3D evaluation of 59 scanned plaster casts of newborn patients with CLP. RESULTS: This work allowed us to obtain digital impression trays for each anatomical variation of orofacial clefts. These trays will limit the problems linked to conventional techniques for making neonatal orthopedic plates. We also emphasized the importance of a multidisciplinary approach involving several professionals in Morocco from various fields and specialties. CONCLUSION: This original technique is advantageous for the practitioner as well as for the patients and their parents. It allows for precise recording, better adaptation, time-saving, and parental comfort.

Changes in the arch width and buccal corridor after fixed orthodontic treatment with Damon self-ligating system: premolar extraction vs. non-extraction

ABSTRACT Introduction: Extraction vs. non-extraction is a crucial decision in orthodontic therapy. Objective: The aim of the present study was to investigate the changes in the dental arch width and buccal corridor after orthodontic treatment using extraction and non-extraction therapy with Damon self-ligating system. Material and Methods: This retrospective study consisted of 35 patients (20 female and 15 male patients with median age of 12.5 years), treated by extracting 4 or 2 premolars, and 37 patients (16 female and 21 male patients with the median age of 12.8 years), treated without premolar extraction. Both groups were treated with Damon self-ligating system. Plaster models before (T0) and after (T1) treatment were measured, and the arch width values were determined at the level of the first molars, second premolars, canines and palatal rugae. Buccal corridor width was measured using the extraoral images at T0 and T1. Paired t-test was used for the analysis of the normally distributed data, and Wilcoxon Mann-Whitney U test was used for the data with non-normal distribution. Values of p<0.05 were set as statistically significant. Results: The upper intercanine width increased significantly in both groups (p<0.01). In the non-extraction group, the arch width increased significantly in the maxillary second premolar and first molar region (p<0.01) as well as in the region of the canines (p=0.04), second premolars (p=0.01) and first molars (p<0.01) of the mandible. The buccal corridor decreased significantly in the non-extraction group (p<0.01). Conclusion: Premolar extraction in combination with Damon self-ligating system did not lead to reduction of the dental arch width in the maxilla, nor did it increase the size of the buccal corridors.

RESUMO Introdução: Extrair ou não extrair dentes é uma decisão crucial no tratamento ortodôntico. Objetivo: O objetivo do presente estudo foi investigar as alterações na largura da arcada dentária e no corredor bucal após o tratamento ortodôntico com extração e o tratamento sem extração com o sistema autoligável Damon. Material e Métodos: Esse estudo retrospectivo consistiu de 35 pacientes (20 do sexo feminino e 15 do sexo masculino, com idade média de 12,5 anos), tratados com extração de 4 ou 2 pré-molares; e 37 pacientes (16 do sexo feminino e 21 do sexo masculino, com idade média de 12,8 anos), tratados sem extração de pré-molares. Ambos os grupos foram tratados com o sistema autoligável Damon. Os modelos de gesso antes (T0) e depois (T1) do tratamento foram medidos, e os valores de largura da arcada foram determinados ao nível dos primeiros molares, segundos pré-molares, caninos e rugas palatinas. A largura do corredor bucal foi medida usando as imagens extrabucais em T0 e T1. O teste t pareado foi usado para a análise dos dados com distribuição normal, e o teste U de Wilcoxon Mann-Whitney foi usado para os dados com distribuição não normal. Valores de p < 0,05 foram considerados estatisticamente significativos. Resultados: A distância intercaninos superiores aumentou significativamente em ambos os grupos (p<0,01). No grupo sem extração, a largura da arcada aumentou significativamente na região dos segundos pré-molares e primeiros molares superiores (p<0,01), bem como na região dos caninos (p=0,04), segundos pré-molares (p=0,01) e primeiros molares (p<0,01) inferiores. O corredor bucal diminuiu significativamente no grupo sem extração (p<0,01). Conclusão: A extração de pré-molares em combinação com o sistema autoligável Damon não levou à redução na largura da arcada dentária superior, nem aumentou o tamanho dos corredores bucais.

Patrón de variación de la forma del arco dentario mandibular en una muestra de la Región Metropolitana de Chile

Objetivos: Describir el patrón de variación de la forma de la arcada dentaria mandibular en una muestra de la Región Metropolitana mediante un estudio observacional, transversal. Métodos: Se digitalizaron 18 puntos de referencia en 134 fotografías estandarizadas de modelos de yeso y se realizó un análisis de Procusto para obtener los componentes de variación de la forma y el tamaño (tamaño del centroide= cs). Resultados: El tamaño de centroide en hombres es significativamente mayor que en mujeres. El análisis discriminante con validación cruzada no mostró diferencias significativas en los componentes de la forma según el sexo. Las diferencias en la forma de los arcos dentales, explicada por los dos primeros componentes de la forma correspondió al 73.4% de la varianza total (PC1= 50,14%, en el eje anteroposterior y PC2= 13,31% en el eje transversal). Conclusiones: De acuerdo con los resultados del presente estudio, se debe replantear el uso de plantillas preformadas en la determinación de la forma del arco dentario, dada la continuidad morfológica que se observa al realizar un análisis estadístico del patrón de variación en forma y tamaño del arco, como queda en evidencia al utilizar herramientas de morfometría geométrica.

Objetivos : Descrever o padrão de variação da forma do arco dentário mandibular em uma amostra populacional da Região Metropolitana, através de um estudo observacional transversal. Métodos : 18 pontos anatómicos em 134 fotografias padronizadas de moldes de gesso foram digitalizados e foi realizado uma análise Procrustes. Resultados : O tamanho do centróide nos homens é significativamente maior do que nas mulheres. A análise discriminante com validação cruzada de gênero não mostrou diferenças significativas nos componentes da forma. O padrão de variação na forma das arcadas dentárias é explicado principalmente por PC1 (50,1% da variação total, variação anteroposterior) e PC2 (13,3%, variação transversal). Conclusões : Dada a continuidade morfológica que se observa ao realizar uma análise estatística do padrão de variação da forma e tamanho da arcada, aplicando ferramentas morfométricas geométricas, o uso de templates pré-formados para determinação da forma da arcada dentária deve ser reconsiderado.

Objectives: Describe the pattern of shape variation of the mandibular dental arch in a sample from the Metropolitan Region through an observational, cross-sectional study. Methods: 18 landmarks on 134 standardized photographs of dental casts were digitized, and a Procrustes analysis was performed. Results: The size of the centroid in men was significantly larger than in women. Discriminant analysis with gender cross-validation did not show significant differences in the shape components. The variation pattern in the shape of the dental arches is mainly explained by PC1 (50.1% of the total variation, anteroposterior variation) and PC2 (13.3%, transverse variation). Conclusions: Given the morphological continuity that is observed when performing a statistical analysis of the variation pattern in shape and size of the arch applying geometric morphometric tools, the use of preformed templates for determining the shape of the dental arch should be reconsidered.

Correlation Theory of the Maxillary Central Incisor, Face and Dental Arch Shape in the Serbian Population.

Background and Objectives: According to the modified Williams theory, the shape of the maxillary central incisor corresponds to the shape of the maxillary alveolar ridge (dental arch) and the shape of the face. Moreover, the standards of beauty suggest that the center of the face of an individual with a full set of teeth should match the center of the maxillary and mandibular dental arches. The purpose of this study is to conduct a comparative cross-sectional study on the matching of the shape of the face, maxillary central incisor and maxillary dental arch as well as the matching of the midfacial line and dental arches in subjects with complete dentition. Materials and Methods: The study included 90 subjects of both sexes. The matching of the shape of the face and midfacial line, i.e., dental arches and maxillary incisors, was determined by analysing photographs, whereas the shape of the dental arch was determined by analysing plaster models. Results: No significant gender-related differences were found either in the shape of the maxillary central incisor that matched the shape of the maxillary dental arch (p = 0.349) or in the shape of the dental arch that matched the shape of the face (p = 0.697). However, a significant difference was noted in the shape of the teeth that matched the shape of the face (p = 0.043), which was more significantly impaired in men. In addition, the matching of the mid-face and the mid-dental arch was significantly greater in women (p = 0.016). Conclusions: The modified Williams theory was confirmed in most subjects, thus it can be considered a relevant guideline when determining the shape of teeth after their loss. The highest percentage of matching in both sexes was with the shape of the face and dental arch. There was no positive correlation between the middle of the maxillary and mandibular dental arch in most cases.

Relación entre la compresión maxilar y potencial impactación del canino superior: Scoping review

El canino maxilar permanente corresponde al segundo diente más frecuentemente impactado en el arco dental. La etiología de esta patología aún no está totalmente definida, sin embargo, investigadores plantean la deficiencia del ancho del hueso maxilar como una posible causa. Objetivo: Investigar la evidencia que asocia menores dimensiones transversales del maxilar a la ocurrencia de la impactación de caninos superiores y esclarecer la posible relación. Materiales y métodos: Se realizó una revisión sistemática exploratoria a partir de una búsqueda amplia de la literatura en bases de datos PubMed, Cochrane, EBSCO y Multibuscador UNAB. Los artículos fueron recopilados, identificados y filtrados según el diagrama de flujo de declaración PRISMA. Resultados: La búsqueda identificó 755 estudios, de los cuales 14 fueron incluidos. Los estudios varían en diseño, edad de estudio y métodos de diagnóstico. La mitad de los estudios reporta una asociación positiva entre compresión maxilar e impactación canina superior, mientras que la otra mitad una asociación negativa. Conclusiones: No hay evidencia suficiente para poder asociar compresión maxilar con impactación de caninos superiores. Estudios con métodos de diagnóstico rigurosos son necesarios para una mejor comprensión. No obstante, se enfatiza la importancia de un diagnóstico precoz, para garantizar mejores resultados y pronóstico más favorable.

The permanent maxillary canine is the second most frequently impacted tooth in the dental arch. The etiology of this disease is not completely defined, yet some researchers propose the deficiency of the width from the maxilla as a possible cause. Objective: To investigate available evidence correlating smaller transverse maxilla dimensions with the occurrence of potential impaction of upper canines and clarify the possible relation. Materials and methods: A systematic exploratory review was carried out based on comprehensive search of the literature in databases such as PubMed, Cochrane, EBSCO and UNAB multi search engine. The articles were compiled, identified and filtered systematically according to the PRISMA flow diagram. Results: Our search identified 755 studies, 14 of which were included. These studies vary in design, patients age, and methods for detection. Half of the studies show a positive correlation between maxillary compression and potential upper canine impaction, whereas the other half show a negative correlation. Conclusions: There is not enough evidence to link maxillary compression to upper canine impaction. Studies with rigorous diagnostic methods for detection are necessary for a better understanding of this relation. Nonetheless, the importance of early diagnosis must be emphasized to guarantee better results and a more favorable prognosis.

Orthodontic Implementation of Machine Learning Algorithms for Predicting Some Linear Dental Arch Measurements and Preventing Anterior Segment Malocclusion: A Prospective Study.

Background and Objectives: Orthodontics is a field that has seen significant advancements in recent years, with technology playing a crucial role in improving diagnosis and treatment planning. The study aimed to implement artificial intelligence to predict the arch width as a preventive measure to avoid future crowding in growing patients or even in adult patients seeking orthodontic treatment as a tool for orthodontic diagnosis. Materials and Methods: Four hundred and fifty intraoral scan (IOS) images were selected from orthodontic patients seeking treatment in private orthodontic centers. Real inter-canine, inter-premolar, and inter-molar widths were measured digitally. Two of the main machine learning models were used: the Python programming language and machine learning algorithms, implementing the data on k-nearest neighbor and linear regression. Results: After the dataset had been implemented on the two ML algorithms, linear regression and k-nearest neighbor, the evaluation metric shows that KNN gives better prediction accuracy than LR does. The resulting accuracy was around 99%. Conclusions: it is possible to leverage machine learning to enhance orthodontic diagnosis and treatment planning by predicting linear dental arch measurements and preventing anterior segment malocclusion.

Influence of presurgical nasoalveolar molding (PNAM) treatment in maxillary dental arch width and nasolabial symmetry in patients with unilateral complete cleft lip and palate.

Unilateral complete cleft lip and palate (UCCLP) is one of the most severe clinical subphenotypes among nonsyndromic cleft lip and/or palate (NSCL/P), that complicates surgical repair operations. Presurgical nasoalveolar molding (PNAM) is a technique used to reshape the nose, lip and alveolar bone of infants with UCCLP before surgery (the modified Mohler rotation advancement cheiloplasty and two flap palatoplasty), with the potential to facilitate surgical repair. However, the effectiveness of PNAM treatment is still a matter of debate. In this paper, the 3Shape scanning system and 3dMD stereophotography were used to assess the short-term and long-term effects of PNAM treatment on the dental arch morphology and nasolabial features of patients with UCCLP, respectively. The findings indicated that PNAM treatment negatively affects both short-term and long-term dental arch shape compared to the treatment without PNAM, particularly in terms of limiting the transverse width of the maxillary canine-to-midline. Regarding the nasal and labial symmetry, PNAM improves the symmetry of the nasal alae in patients over 7 years old and the symmetry of the lip in patients under 7 years old. Moreover, UCCLP patients who received PNAM treatment exhibited a shorter and wider shape of the nostril on the cleft side compared to those without PNAM treatment. In clinical practice, the multidisciplinary team should carefully consider the advantages and disadvantages of the outcomes of PNAM treatment when treating infants with cleft lip and palate.

Assessment of early dental arch growth modification with removable maxillary expansion by cone-beam computed tomography and lateral cephalometric radiographs: a retrospective study.

BACKGROUND: This study evaluated the skeletal and dental changes of patients brought by early removable maxillary expansion (ERME) treatment to explore the clinical treatment effect of ERME on early dental arch growth modification. METHODS: Subject children aged 6-10 years with a maxillary transverse deficiency received ERME treatment, cone-beam computed tomography (CBCT) and lateral cephalometric radiographs were measured before and after treatment, and statistical differences in the measured items were evaluated with corresponding statistical methods to explore the skeletal and dental changes. RESULTS: After ERME treatment, there was a statistical increase in the maxillary basal bone arch width, nasal cavity width, maxillary alveolar bone arch width, and maxillary dental arch width. A buccal inclination of the maxillary alveolar bone and a buccal inclination and buccal movement in the alveolar bone of maxillary first molars were found. The maxillary skeletal expansion was statistically greater than the dental expansion. Increases in the mandibular alveolar bone arch width and dental arch width happened after treatment. A decrease in angle ANB and an increase in Ptm-A, U1-SN, U1-PP, L1-MP, and L6-MP were found after treatment. No statistical changes in the growth pattern-related measured items were observed. CONCLUSIONS: ERME could expand the maxillary basal bone arch width, nasal cavity width, maxillary alveolar bone arch width, and maxillary dental arch width. The maxillary skeletal expansion was greater than the dental expansion. Secondary increases in the mandibular alveolar bone and dental arch widths would happen after ERME. ERME would result in a mandibular advancement, a labial inclination of maxillary anterior teeth, and an increase of maxillary sagittal length, and would not change the patient's growth pattern. TRIAL REGISTRATION: This study was approved by the Institutional Review Board of the West China Hospital of Stomatology, Sichuan University. (WCHSIRB-D-2020-446).

Accuracy of models of partially edentulous arches obtained by three-dimensional printing: An in vitro study.

Aim: The aim of this study was to evaluate the accuracy of models of partially edentulous arches obtained by three-dimensional (3D) printing. Settings and Design: This was an in vitro study. Materials and Methods: Fifteen partially edentulous models were evaluated, using two methods of measuring dimensions: virtual, using the Standard Tessellation Language files of the models and software (control group), and physical, through printing the models and digital caliper (test group). For both methods, measurements were made regarding the dimensions of the teeth (width and length - buccal/lingual or palatal/occlusal) and distances between the teeth. Statistical Analysis Used: For the variable of linear measurements (width and length) and distances between teeth of the same hemiarch, the Wilcoxon test was used, while for the variable between opposite hemiarches, the paired t-test was used. Results: In the evaluation of the linear measurements, a significant difference was observed only when the width of the molar tooth was analyzed (P = 0.014). When the buccal length was measured, all teeth had linear measurements provided by the virtual method that was lower than the physical (P = 0.000), as well as the lingual/palatal length in incisors (P = 0.003) and molars (P = 0.009) and in total (P = 0.001). As for the analyses between teeth, no difference was identified between the measurements provided by the virtual method compared to the physical one. Conclusions: The 3D printer used to print partially edentulous models provided linear distortions in the teeth but without changes in the distances between teeth of the same hemiarch and between teeth of opposite hemiarches.

Heritability of dental arches and occlusal characteristics: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: The genetic basis of dentoalveolar characteristics has been investigated by several studies, however, the findings are equivocal. The objective of this systematic review and meta-analysis was to evaluate the heritability of dental arches and occlusal parameters in different stages of human dentition. SEARCH METHODS: Electronic databases PubMed, Embase, Scopus, Web of Science, and Dentistry and Oral Science Source were searched up to August 2023 without the restriction of language or publication date. SELECTION CRITERIA: Empirical studies investigating the heritability of dentoalveolar parameters among twins and siblings were included in the review. DATA COLLECTION AND ANALYSIS: Study selection, data extraction, and risk of bias assessment were performed independently and in duplicate by two authors and a third author resolved conflicts if needed. Joanna Briggs Institute's critical appraisal tool was used to evaluate the risk of bias among studies and the certainty of evidence was assessed using the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) criteria. RESULTS: Twenty-eight studies were included in the systematic review, of which 15 studies reporting heritability coefficients in the permanent dentition stages were deemed suitable for the meta-analysis. Random-effects meta-analyses showed high heritability estimates for maxillary intermolar width (0.52), maxillary intercanine width (0.54), mandibular intermolar width (0.55), mandibular intercanine width (0.55), maxillary arch length (0.76), mandibular arch length (0.57), and palatal depth (0.56). The heritability estimates for the occlusal parameters varied considerably, with relatively moderate values for crossbite (0.46) and overbite (0.44) and low values for buccal segment relationship (0.32), overjet (0.22), and rotation and displacement of teeth (0.16). However, the certainty of evidence for most of the outcomes was low according to the GRADE criteria. CONCLUSIONS: Based on the available evidence, it can be concluded that the dental arch dimensions have a high heritability while the occlusal parameters demonstrate a moderate to low heritability. REGISTRATION: PROSPERO (CRD42022358442).